Choose Start, Run, and type sysedit (then hit Ok). This should launch the System Configuration Editor. Click the autoexec.bat window first. These programs are automatically executed when you first boot up your PC. In Windows 2000 and XP, you won't likely need any of the programs in the autoexec.bat window, so put REM in front of them. E.g.:

REM C:\WINDOWS\COMMAND\MSCDEX.EXE /D:IDECD000

PATH=%PATH%;CPROGRA~1COMMON~1MUVEET~1030625